8 Seven Segment LED Display with Keys and LEDs using TM1638.

Using the library available from here this board is easy to operate. Connecting the board to an Arduino requires five connections, Vcc to Arduino 5 volts, Gnd to Gnd. STB, CLK and DIO on the display board connect to 7, 9 and 8 on the Arduino.

The library contains a number of examples, but the pins used for Clock, Strobe and Digital Input varies in each example, so I have defined these at the start.
/*TM1638 8 x Seven Segment Display with Keys and LEDs
Tests some functions
No key pressed displays decimal number
Key 1 pressed displays HEX value
Key 2 pressed displays binary value
Key 3 pressed clears displayed
Key 4 pressed displays a text string